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Mars rover’s large methane discovery excites scientists

Nasa’s Curiosity rover has detected its largest belch of methane on Mars so far, fuelling speculation that the robot may have trundled through a cloud of waste gas released by microbial Martians buried deep under the surface.

Mission scientists announced on Monday that Curiosity had measured a record-breaking 21 parts per billion (ppb) of methane in the air in Gale crater, the rover’s landing site and area of exploration. The level is substantially more than the 5.8ppb it sensed on 16 June 2013.

The latest measurement has excited some Mars enthusiasts because on Earth, much of the methane in the air comes from living things that release it one way or another as waste gas. But methane can have far more mundane origins than microscopic Martians, such as reactions between water and certain types of rock, and Nasa’s rover cannot distinguish between these.

While Mars was once warm and home to coursing rivers and giant lakes, it is now exceptionally dry and battered with intense radiation. If any life exists on the planet, it would probably have to be sheltering deep underground.

Read more at The Guardian